Often referred to as the “forgotten organ” thanks to its dramatic impact on our overall health, the human gut microbiome has been and will continue to be a super hot topic, one that all of us should be familiar with and never forget.

Your gut microbiome includes trillions of microbes, including bacteria, fungi and viruses, that regulate the immune system, inflammation, digestion, and much more.

It’s no wonder these bugs have been the focus of many news articles and research studies.

At this point, you might be wondering what, if anything, you can do to optimize your gut microbiome. Recent studies suggest that what we eat and how we live our lives can directly affect our gut microbiome.

Bear in mind that as of right now we don’t know what constitutes a “normal” or “ideal” gut microbiome, but researchers are working hard to solve that puzzle. However, the experts strongly suspect that diversity is key.

All of the following factors have been shown to affect the diversity of our gut flora: age, stress, hygiene, intestinal infections, alcohol, antibiotics, smoking, food, breast milk, and vaginal delivery versus cesarean section.

A recent study from the Netherlands provided a list of factors that correlated with changes in the diversity of the microbiome. Without an advanced degree in microbiology or metagenomics, most of the report is incomprehensible, but I will share with you a few of the key findings without getting too scientific.

These dietary factors were associated with a higher level of diversity (ideal): Coffee, tea, red wine, fruits, vegetables, and buttermilk.

​Researchers suspect that the antioxidants (specifically, polyphenols) in coffee, tea, and wine were responsible for their positive impact on gut flora.

Buttermilk is more popular in the Netherlands than in the US, but perhaps these findings could extend to yogurt or kefir, all fermented dairy products. TBD.

This study found an association between drinking buttermilk and presence of strains of bacteria that ferment dairy, suggesting a potential role for probiotic dairy drinks to alter gut flora.

These next few bullets are a bit “sciency”, but bear with me…

Chromogranin A (CgA) is a peptide that has been shown to be released from cells in response to stress and active GI diseases, including IBS and IBD.

This study showed that low CgA was associated with higher microbial diversity (ideal), high concentrations of HDL cholesterol (aka good cholesterol), and eating fruits and vegetables.

High CgA was associated with higher levels of fecal calprotectin (a marker for intestinal inflammation), high triglycerides (not good), frequent and loose stool, and self-reported IBS.

Low calprotectin (good) was associated with higher intakes of vegetables, plants, and chocolate!

To sum up, these findings suggest that eating fruits, vegetables and other plant foods could help with inflammation and cholesterol management.

A few extra fun facts...

The use of antibiotics was associated with decreases in the composition of certain bacteria.

Proton pump inhibitors (PPIs) and Metformin were correlated with changes in the gut microbiome.

Dietary intake of nuts, fruits, and vegetables correlated with certain bacterial strains that are associated with quality of life, triglycerides and HDL cholesterol.

While these findings are interesting and suggest ways for us to positively modify our gut flora, these findings are very new and the research is limited.

Until more research is done, at a minimum we know that what we eat directly affects our gut microbiome. Eating a wide variety of whole foods, mostly plant foods, limiting highly processed foods and added sugar, and avoiding sugar-sweetened beverages are steps you can take now to support a healthy gut microbiome.